1. Field of the Invention
The invention relates generally to a protective helmet and a motion restrictor device adapted for use with a protective helmet, and in particular, but not limited to a football helmet.
2. Description of the Related Art
Various activities, such as snowmobile riding, lacrosse, hockey, motocross, supercross, motorcycle riding, automobile racing, go-cart riding, automobile racing, snowboarding, snowskiing, aircraft flying, bicycle riding, pole vaulting and contact sports and in particular the sport of football, require the use of helmets to attempt to protect participants from injury to their heads due to impact forces that may be sustained during such activities. Various types of helmets have been in use in the sport of football, ever since individuals began wearing helmets to attempt to protect their heads many years ago. Typically, these helmets have included: an outer shell, generally made of an appropriate plastic material, having the requisite strength and durability characteristics to enable them to be used in the sport of football; some type of shock absorbing liner within the shell; a face guard; and a chin protector, or chin strap, that fits snugly about the chin of the wearer of the helmet, in order to secure the helmet to the wearer's head, as are all known in the art.
In an attempt to minimize cervical spine injuries, such as football-related cervical spine injuries, various protective helmets, such as football helmets have been suggested which include some structure to secure the helmet to the shoulder pads worn by the football player. In general, most of the previously proposed football helmets suffer from various disadvantages resulting from: the bulkiness and/or unwieldy nature of the components utilized with the helmet; inadequate support of the helmet with respect to the shoulder pads; and not having the ability to substantially restrict, or prevent, relative motion between the helmet and the player's shoulders. In general, the cervical spine injuries suffered by football players are caused by axial loading of the cervical spine, or the application of a compressive force upon the spine in a direction generally parallel to the longitudinal axis of the football player's spine. Thus, the rules of football were modified in 1976 by the National Collegiate Athletic Association and the National Federation of State High School Athletic Associations to ban “spearing” of an opposing player by a player utilizing his football helmet. Those rule changes have reduced the number of cervical spine injuries in the sport of football, but every year there are still a number of these types of injuries, which may have a catastrophic impact upon the player suffering such an injury. The football player typically goes from being an active, healthy teenager or young adult to a quadriplegic, dependent upon others for even the most basic of human bodily functions. These former players may endure a life of limited mobility, potentially limited experiences, recurrent infections, and a potentially shortened life span. Millions of dollars in health care related costs are expended in treatment and care of these individuals, and in addition each affected family suffers an emotional and psychological toll resulting from such injury.
While the intentional offensive use of a football helmet to butt or spear the player's opponent is many times the cause of a cervical spine injury, many of these injuries resulting from an axial load upon the player's spine, occur when a player is tackling an opponent with his head unintentionally lowered. While tackling techniques are widely taught in high schools across the nation, a player's natural reflex is to drop his head at the point of contact, rather than to watch the collision occur a few inches from his face as the opponent's body may strike the tackler's facemask.
The normal lordotic curve of the cervical spine is believed to be a protective mechanism, because the cervical spine is able to dissipate a blow to the head by hyper-extending without injury. It is believed that when the lordotic curve is straightened, as may occur when a football player's head is lowered, this potential protective mechanism may be lost. If the axial load, or force, upon the top, or crown, of a player's head is large enough, the disruption of the ligaments of the cervical spine, or even a burst fracture of the cervical vertebrae may occur as the energy is dissipated. These injuries may result in severe injury of the very fragile nerve tissue of the spinal cord, and paralysis may often result from the injury.
While it is the desire and goal that a football helmet, and other types of protective helmets, prevent injuries from occurring, it should be noted that as to the helmet of the present invention, due to the nature of the sport of football in particular, no protective equipment or helmet can completely, totally prevent injuries to those individuals playing the sport of football or wearing any protective helmet. It should be further noted that no protective equipment can completely prevent injuries to a player, if the football player uses his football helmet in an improper manner, such as to butt, ram, or spear an opposing player, which is in violation of the rules of football. Improper use of a helmet to butt, ram, or spear an opposing player can result in severe head and/or neck injuries, paralysis, or death to the football player, as well as possible injury to the football player's opponent. No football helmet, or protective helmet, such as that of the present invention, can prevent head, chin, or neck injuries a football player might receive while participating in the sport of football. The helmet of the present invention is believed to offer protection to football players, but it is believed that no helmet can, or will ever, totally and completely prevent head, neck, or spine injuries to football players.
The protective helmet of the present invention and motion restrictor device for use with a protective helmet, when compared to previously proposed protective helmets and motion restrictor devices have the advantages of: being designed to attempt to protect a wearer of the helmet from injuries caused by an impact force striking the top, or crown, of the helmet and acceleration of the helmet beyond a safe threshold; not being bulky and unwieldy to wear, and difficult to use; provides a substantially complete free range of movement, within normal anatomic limits of head and neck movement, of the helmet until an impact force, beyond a predetermined amount, is applied to the top of the helmet or an acceleration of the helmet greater than a predetermined amount of or rate of acceleration is detected by an acceleration sensor; and, upon sustaining a force equal to, or greater than the predetermined amount, or an acceleration equal to or greater than the predetermined amount of acceleration or rate of acceleration, the motion restrictor device of the helmet locks to substantially prevent relative motion of the helmet with respect to the player wearing the helmet; at all times, even when there is no force on the helmet, hard stops or abutments are in place that limit the range of motion between the first and second ends of the at least one strut member and other abutments are in place that limit the range of motion of the hinging and pivoting connectors that connect the strut members to the helmet and similar abutments are also in place that limit the range of motion of the hinging and pivoting connectors that connect the strut members to the shoulder harness thus limiting the range of motion of the helmet and cervical spine protection device to the normal, non-injurious range of motion of the head and neck of the wearer and help prevent injuries related to hyper-flexion, lateral-flexion, hyper-extension and rotation of the head and neck beyond normal anatomic movement; the acceleration sensor use in the protective helmet also aids in attempting to prevent or reduce the severity of head and brain injury by substantially stopping head and neck movement with respect to the chest, back and shoulders of the individual wearing the protective helmet by locking the motion restrictor device of the helmet when a predetermined amount of acceleration or rate of acceleration of the helmet is exceeded.